net: mdio: common handling of phy device reset properties

net: mdio: common handling of phy device reset properties

Unify the handling of the per device reset properties for
`mdio_device`.

Merge mdio_device_register_gpiod() and mdio_device_register_reset()
into mdio_device_register_reset(), that handles both
reset-controllers and reset-gpios.
Move reading of the reset firmware properties (reset-assert-us,
reset-deassert-us) from fwnode_mdio.c to mdio_device_register_reset(),
so all reset related initialization code is kept in one place.

Introduce mdio_device_unregister_reset() to release the associated
resources.

These changes make tracking the reset properties easier.
Added kernel-doc for mdio_device_register/unregister_reset().

Signed-off-by: Buday Csaba <buday.csaba@prolan.hu>
Link: https://patch.msgid.link/17c216efd7a47be17db104378b6aacfc8741d8b9.1763473655.git.buday.csaba@prolan.hu
Signed-off-by: Jakub Kicinski <kuba@kernel.org>